Physical oceanography of the Ningaloo Marine Park, Western Australia (WAMSI Node 3 Project 3.1.6)

Ningaloo Reef is a unique fringing reef, the largest in Australia and one of the most biologically diverse of shallow water marine ecosystems. An intensive oceanographic field study, during April-May 2006, focused on a stretch of reef approximately 5km in length, located in the Sandy Bay region of the Ningaloo Marine Park (NMP). The reef morphology in this region is typical of the Ningaloo system with a simple configuration of shore-parallel reef sections, punctuated by deeper channels, oriented perpendicular to the reef crests. The field study measured key hydrodynamic variables at 25 sites spanning the lagoonal waters to the front reef slopes.This project delivers an enabling data set on the dominant oceanographic processes in the NMP. It is envisaged that this data set will provide the basis on which further modeling and bio-physical studies will be built, with the ultimate goal of developing a system-wide understanding of the physical processes in the marine park and how they influence ecological processes and biodiversity. The hydrodynamic processes that have shaped the patterns of biodiversity at Ningaloo Reef are poorly described. Existing knowledge has been generated through a small number of spatially and temporally limited studies, and as such does not provide the system-wide understanding of the hydrodynamics and their influence on key ecological processes that is needed to develop robust management plans and strategies. The observational array included wave gauges and single point current meters deployed along cross-reef transects from the reef slope into the lagoons, and current profilers deployed within the deep channels. A number of bottom mounted temperature loggers were also deployed within a reef channel to provide data on intrusions (upwelling) of cooler oceanic water and the development and destruction of thermal stratification. Offshore current conditions, including the interaction of the Leeuwin and Ningaloo currents and their annual and interannual variability were monitored by two existing AIMS moorings offshore from the Tantabiddi reef channel. The mooring sites are located in water depths of 100m and 50m and have been occupied contiguously since 1999.

宁格罗礁（Ningaloo Reef）是一处独特的岸礁（fringing reef），为澳大利亚境内规模最大的岸礁，同时也是全球生物多样性最为丰富的浅海海洋生态系统之一。2006年4-5月期间，科研团队开展了密集的海洋学野外调查，聚焦于宁格罗海洋公园（Ningaloo Marine Park, NMP）桑迪湾区域一段长约5公里的礁体区段。该区域的礁体形态为宁格罗礁系统的典型代表，呈现与岸线平行的礁体区段简单构型，其间穿插有垂直于礁脊的深水通道。本次野外调查在从潟湖水域到礁前斜坡的25个测点上测量了关键水动力变量。本项目提供了涵盖宁格罗海洋公园内主要海洋学过程的支撑性数据集，旨在为后续模拟与生物物理研究提供基础，最终目标是全面理解该海洋公园内的物理过程及其对生态过程与生物多样性的影响。此前对塑造宁格罗礁生物多样性分布格局的水动力过程的描述极为匮乏，现有认知仅来自少量空间与时间尺度均有限的研究，因此无法提供制定完善的管理规划与策略所需的、关于水动力过程及其对关键生态过程影响的全域性认知。本次观测阵列包含沿跨礁断面（从礁坡延伸至潟湖）布设的波潮仪与单点海流计，以及在深水通道内布设的海流剖面仪。另有若干海底温度记录仪部署于一处礁体通道内，用于获取冷大洋水侵入（上升流）以及热层结形成与消散的相关数据。两处现有澳大利亚海洋科学研究所（Australian Institute of Marine Science, AIMS）锚系观测站，对塔比迪礁通道外海的海流条件进行监测，监测内容涵盖勒温海流与宁格罗海流的相互作用及其年内与年际变化。这两处锚系站点的水深分别为100米与50米，自1999年起便持续开展观测。